package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import net.sf.jsqlparser.expression.StringValue;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Component;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock {

    private String name;
    private StringRedisTemplate stringRedisTemplate;

    public SimpleRedisLock(String name, StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }

    private static final String KEY_PREFIX = "lock:";
    private static final String ID_PREFIX = UUID.randomUUID().toString(true) + "-";
    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;

    static {
        UNLOCK_SCRIPT = new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }

    @Override
    // 尝试获取锁
    public boolean tryLock(Long timeoutSet) {
        String threadId =  ID_PREFIX + Thread.currentThread().getId();
        Boolean flag = stringRedisTemplate.opsForValue().setIfAbsent(KEY_PREFIX + name, threadId, timeoutSet, TimeUnit.SECONDS);

        return flag != null && flag ;
    }

    @Override
    // 释放锁
    public void unLock() {

        stringRedisTemplate.execute(
                UNLOCK_SCRIPT, Collections.singletonList(KEY_PREFIX + name), ID_PREFIX + Thread.currentThread().getId()
        );

//        String threadId =  ID_PREFIX + Thread.currentThread().getId();
//        String threadIdStr = stringRedisTemplate.opsForValue().get(KEY_PREFIX + name);
//        if (threadId.equals(threadIdStr)) {
//            stringRedisTemplate.delete(KEY_PREFIX + name);

    }
}
